This is a puzzle with 9! possibilities and 336 solutions. The problem posed in 9 digits consists in the organization of the numbers 1 to 9 in a square of 3 * 3 to make the sum of the numbers of the fi...More: lessons, discussions, ratings, reviews,...

KenKen is a grid-based logic puzzle and math game. For a 3x3 puzzle, use the numbers 1-3; for a 4x4 puzzle, fill in with numbers 1-4; for a 5x5 puzzle, use the numbers 1-5, and so on. Do not repeat a ...More: lessons, discussions, ratings, reviews,...

Puzzle with 9! possibilities and 336 solutions. The problem posed in Ninedigits workshops consists in the organization of the numbers 1 to 9 in a square of 3 * 3 to make the sum of the numbers of the...More: lessons, discussions, ratings, reviews,...

The fundamental theorem of arithmetic, also known as the unique factorization theorem or the unique-prime-factorization theorem, states that every integer greater than 1 either is prime itself or is t...More: lessons, discussions, ratings, reviews,...

Use the menus and text boxes to create your own quizzes on addition, subtraction, multiplication, and division -- or browse from among a selection. Click the appropriate button to reveal answers, grad...More: lessons, discussions, ratings, reviews,...

Alterable worksheet in which students estimate the positions of points on unmarked number lines, on the intervals [0, 100], [0,1000], [-10, 0], [-100, 0]. Fee required for printing: see this page.More: lessons, discussions, ratings, reviews,...

The user trains multiplication skills. Homer Simpson inspires the user to learn multiplication. Game runs in two modes. In case of wrong answer it displays the right one. Game is time limited.More: lessons, discussions, ratings, reviews,...

This material is based upon work supported by the
National Science Foundation under Grant DUE-0226284.
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